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101.
本文研究一类非线性趋化方程的局部能控性和时间最优控制的存在性问题.该方程不仅具有非线性的drift-diffuion项?·(χu?v),而且具有非线性的细菌消耗项uf(v).研究该方程主要运用了相应线性方程的零能控性和Kakutani不动点定理的方法. 相似文献
102.
Almost all natural, social and man-made-engineered systems can be represented by a complex network to describe their dynamic behaviors. To make a real-world complex network controllable with its desired topology, the study on network controllability has been one of the most critical and attractive subjects for both network and control communities. In this paper, based on a given directed–weighted network with both state and control nodes, a novel optimization tool with extremal dynamics to generate an optimal network topology with minimum control nodes and complete controllability under Kalman’s rank condition has been developed. The experimental results on a number of popular benchmark networks show the proposed tool is effective to identify the minimum control nodes which are sufficient to guide the whole network’s dynamics and provide the evolution of network topology during the optimization process. We also find the conclusion: “the sparse networks need more control nodes than the dense, and the homogeneous networks need fewer control nodes compared to the heterogeneous” (Liu et al., 2011 [18]), is also applicable to network complete controllability. These findings help us to understand the network dynamics and make a real-world network under the desired control. Moreover, compared with the relevant research results on structural controllability with minimum driver nodes, the proposed solution methodology may also be applied to other constrained network optimization problems beyond complete controllability with minimum control nodes. 相似文献
103.
陈万吉 《应用数学和力学(英文版)》1986,7(5):481-487
According to recent studies of the generalized variational principle by Professor Chien Weizang, the more generalized hybrid variational principle for finite element method is given, from which a new kind of the generalized hybrid element model is etablished.Using the thin plate bending element with varying thickness as an example, we compare various hybrid elements based on different generalized variational principles. 相似文献
104.
105.
We show that the Moore–Gibson–Thomson equation is controlled by a force that is supported on an moving subset of the domain, satisfying a geometrical condition. Using the concept of approximately outer invertible map, a generalized implicit function theorem and assuming that , the local null controllability in the nonlinear case is established. Moreover, the analysis of the critical value for the linear equation is included. 相似文献
106.
This work deals with the guidance and control of a system which is composed of a rolling disk and a controlled slender rod that is pivoted, through its center of mass, about the disk center. There are given N points P
i, i=1, ..., N, in the horizontal plane, a set of angles 2i
, i=1, ..., N, a finite-time interval [0, t
f], and a sequence of times 1=0<2<...<
N
=t
f. Using the concept of path controllability, a closed-loop control law is derived to steer the system in such a manner that the disk center and the rod angle of rotation 2 will pass through (P
i, 2i
) at the times
i
, i=1,...,N, respectively. This system serves as a model for the motion of a simple mobile robot. 相似文献
107.
Szymon W?sowicz 《Journal of Mathematical Analysis and Applications》2007,332(2):1229-1241
It is well known that every convex function (where I⊂R is an interval) admits an affine support at every interior point of I (i.e. for any x0∈IntI there exists an affine function such that a(x0)=f(x0) and a?f on I). Convex functions of higher order (precisely of an odd order) have a similar property: they are supported by the polynomials of degree no greater than the order of convexity. In this paper the attaching method is developed. It is applied to obtain the general result—Theorem 2, from which the mentioned above support theorem and some related properties of convex functions of higher (both odd and even) order are derived. They are applied to obtain some known and new Hadamard-type inequalities between the quadrature operators and the integral approximated by them. It is also shown that the error bounds of quadrature rules follow by inequalities of this kind. 相似文献
108.
109.
陈应天 《应用数学和力学(英文版)》1983,4(3):431-434
The general form of J-integral conservation law in three di-mensions has been derived from the principle of virtual work.The necessary conditions for J-integral conservation are alsogiven. 相似文献
110.